Old-timers as myself already saw this coming.
The main idea of killing Flash was because some websites completely ran on it, which is bad. But games never was an issue, and never will be.
Battery life, system resources, downloading assets, ..., it's all the same if you use either Flash or JavaScript.
Newsflash: Apple didn't block Flash because it is "bad", they blocked it because they wanted you to go through their app store
Newsflash: Games written for Flash (in ActionScript3) also run on Android and iOS. It even became "Best Mobile Application Development product" of 2014 and 2015.
They say Flash advertisement banners were annoying, so what do you think about those JavaScript popup banners that pop in the middle of the page you are reading, saying "Please subscribe to our mailing list"?
I you develop a game for Flash, it runs consistently in the Flash plugin. If you develop a game in JavaScript, you need to test it in all browsers you want to support. And yes, they are all different. And still gives troubles so many years later. Surprising? Not for old farts like myself.
But no worries. I looked at my google analytics for the past few years. Most visitors moved to Chrome. Flash plugin installed percentage: remained the same.